What does junior high school mean?

Junior high school is a term for a type of secondary school that typically encompasses grades 7, 8, and sometimes 9. It sits between elementary school and senior high school (or high school). The term is less common now than it used to be, as many school districts have reorganized their middle schools to encompass a similar range of grades. The exact grade levels and the name used (middle school, junior high, etc.) vary by location.